HL7 RAR_RAR (Pharmacy/Treatment Administration Information)

HL7 RAR_RAR Pharmacy/Treatment Administration Information

The old-style query response for medication administrations.

HL7 message structure RAR_RAR groups and segments from HL7 v2.5.1 Hide structure

These are the generated groups and segments for the version selected at the top of the page. The article explains the workflow, and this panel follows the chosen HL7 version.

Message Structure

Segment	Name	Required	Repeatable
MSH	Message Header	Yes	No
MSA	Message Acknowledgment	Yes	No
ERR	Error	No	Yes
SFT	Software Segment	No	Yes
RAR_RAR.DEFINITION	Definition group	Yes	Yes
QRD	Original-Style Query Definition	Yes	No
QRF	Original style query filter	No	No
RAR_RAR.PATIENT	Patient group	No	No
PID	Patient Identification	Yes	No
NTE	Notes and Comments	No	Yes
RAR_RAR.ORDER	Order group	Yes	Yes
ORC	Common Order	Yes	No
RAR_RAR.ENCODING	Encoding group	No	No
RXE	Pharmacy/Treatment Encoded Order	Yes	No
RXR	Pharmacy/Treatment Route	Yes	Yes
RXC	Pharmacy/Treatment Component Order	No	Yes
RXA	Pharmacy/Treatment Administration	Yes	Yes
RXR	Pharmacy/Treatment Route	Yes	No
DSC	Continuation Pointer	No	No

RAR_RAR returns pharmacy or treatment administration information in response to an original-style HL7 query. In practice, this is the older query-response companion to administration workflows such as RAS_O17.

Use it when a receiver asks, "what was administered?" and the responder needs to return administration facts, not a new administration event.

A small RAR RAR example

MSH|^~\&|PHARMACY|CITYHOSP|EHR|CITYHOSP|20260723130000||RAR^RAR^RAR_RAR|RAR00001|P|2.5.1 MSA|AA|QRYRAR001 QRD|20260723125900|R|I|QRYRAR001|||1^RD|123456^^^CITYHOSP^MR|RXA^Administration history^L|MEDADMIN|T PID|1||123456^^^CITYHOSP^MR||Rivera^Maya^^^^^L||19750519|F ORC|RE|ORD448811^EHR|RX990201^PHARMACY|GRP448811|CM RXE||AMOX500^Amoxicillin 500 mg capsule^L|500||mg^milligram^UCUM|CAP^Capsule^L RXR|PO^Oral^HL70162 RXA|1|1|20260723090000|20260723090000|AMOX500^Amoxicillin 500 mg capsule^L|500|mg^milligram^UCUM|||NURSE01^Lane^Priya RXR|PO^Oral^HL70162

What workflow it represents

A requesting system has asked for administration history or administration detail. The responding pharmacy, eMAR, or clinical system returns one or more orders with the matching administrations.

Do not confuse this with sending a new administration event. RAR_RAR answers a query; RAS-style messages report administrations as workflow events.

How to read the structure

The response envelope starts with MSH, required MSA, optional ERR, and optional SFT.

Each DEFINITION group carries required QRD and optional QRF, then optional patient context in PID. Each ORDER group starts with ORC.

Optional encoded order context appears in RXE, RXR, and RXC. The administration facts are in repeating RXA rows, followed by the required administration route in RXR. Optional DSC supports continuation.

Implementation traps

Administration time is not dispense time and not order entry time. Keep RXA administration dates separate from the order and pharmacy fill dates.

If the response is paged, do not build a partial medication history from only the first response. DSC continuation handling matters here.

Also be careful with optional encoded order context. RXE is useful for comparison, but RXA is the administration record the requester usually came for.

Reference notes

HL7 v2.5.1 query listings identify RAR_RAR as pharmacy/treatment administration information. The structure uses the older QRD/QRF query definition pattern with order and administration detail under each definition group.